CN100385813C - Delay searcher and delay trackers interaction for new delays assignment to rake fingers - Google Patents
Delay searcher and delay trackers interaction for new delays assignment to rake fingers Download PDFInfo
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- CN100385813C CN100385813C CNB998119296A CN99811929A CN100385813C CN 100385813 C CN100385813 C CN 100385813C CN B998119296 A CNB998119296 A CN B998119296A CN 99811929 A CN99811929 A CN 99811929A CN 100385813 C CN100385813 C CN 100385813C
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
- H04B1/711—Interference-related aspects the interference being multi-path interference
- H04B1/7115—Constructive combining of multi-path signals, i.e. RAKE receivers
- H04B1/7117—Selection, re-selection, allocation or re-allocation of paths to fingers, e.g. timing offset control of allocated fingers
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
- H04B1/711—Interference-related aspects the interference being multi-path interference
- H04B1/7115—Constructive combining of multi-path signals, i.e. RAKE receivers
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/69—Spread spectrum techniques
- H04B1/707—Spread spectrum techniques using direct sequence modulation
- H04B1/7097—Interference-related aspects
- H04B1/711—Interference-related aspects the interference being multi-path interference
- H04B1/7113—Determination of path profile
Abstract
A direct sequence spread spectrum receiver for operating in a multipath fading channel comprises a rake receiver having plural rake fingers. Each rake finger demodulates a received signal from one of plural channel paths. The output of the plural rake fingers are combined. Each rake finger utilizes a select assigned delay to synchronize to a delay of the one channel path. A searcher periodically performs a channel search on the received signal to detect new delays of strongest paths in the channel. Plural trackers, one for each channel path, adjust the select assigned delays between searches performed by the searcher. A-delay controller is operatively coupled to the searcher and the trackers. The delay controller compares new delays of the strongest paths from the searcher to the select assigned delays and reassigns one of the select assigned delays with one of the new delays only if the new delay differs from the one select assigned delay more than a predetermined threshold.
Description
Invention field
The present invention is relevant with Receiver of Direct-sequence Spread Spectrum, specifically, relates to interactive technology between the delay searcher and delay tracker in postponing for the assignment of Rake (rake) receiver is new.
Background of invention
In a typical radio frequency (RF) communication system, transmit and to propagate into a receiver by a plurality of paths of for example a directapath and a reflection path from a transmitter.An independently channel, the influence that is declined, dissipates or the like can be thought in each path.In addition, some signals combine at receiver and may cause the decline that adds.Such operational environment is called the multipath fading environment.Direct sequence spread spectrum (DS-SS) receiver can be worked in the multipath fading environment.The DS-SS receiver generally includes one and utilizes a plurality of demodulation branch demodulation to received signal that are called rake finger.Each rake finger is to signal component (such signal component the is called multi-path component) demodulation from one of several channel paths.By the output that merges these rake fingers performance is improved.
Under the situation of multi-path channel, one transmits the form arrival with some components, and each component has different delays.These components can be distinguished and differentiate, if it is fully big to postpone difference.Yet for to these signal demodulation, Rake receiver must be known the delay of each channel path.
Usually, Rake receiver has delay searcher and delay tracker cooperating.Delay searcher is analyzed to received signal, finds out these delays.Each rake finger is distributed in these delays.Yet in mobile communication, channel may be subjected to the influence of the additional fading that the motion owing to receiver causes.The delay of delay tracker track-while-scan device appointment between each secondary channel search.Therefore, the searcher inspection postpones on a large scale, and the tracker inspection is a near small range of specifying postponing.
Utilize such configuration, during the assignment again after the once new search, may produce some problems.A problem is that precision reduces after new search.Usually, the used resolution of delay searcher is lower than the delay tracker.When carrying out once new search, delay searcher may be found a path, its delay near but be not identical with the tracker tracking fully.In fact this path may be exactly the same path that delay tracker is followed the tracks of.The resolution of delay searcher is lower so detected delay has difference to be.Yet delay searcher can be specified this new delay for rake finger, thereby causes the lower result of precision before tracker is adjusted new delay subsequently.
Another problem is unnecessary the reorientating that rake finger is postponed.Usually, delay searcher be first rake finger specify one with the delay of the channels associated of arrival the earliest.Equally, the next channel path that arrives is distributed to next rake finger, and so on.Because the fluctuating of the relative signal intensity that the channel path variation can cause, thereby may cause understanding assignment again to another rake finger after the search afterwards of same channel path.This assignment again needs the time, and data may be lost during giving another rake finger with same channel path assignment again.
The objective of the invention is with a kind of novelty simply, mode overcomes above-described one or more problem.
Summary of the invention
According to the present invention, equipment that is disclosed and method utilize the reciprocation of delay searcher and delay tracker to come newly to postpone for the Rake receiver assignment.
Put it briefly, the Receiver of Direct-sequence Spread Spectrum of working in the multipath fading environment that is here disclosed comprises a Rake receiver with a plurality of rake fingers.Each rake finger is to received signal component (i.e. multi-path component) demodulation from one of a plurality of channel paths.The output of these rake fingers is incorporated in together.Each rake finger utilizes one to select specified delay synchronous with the delay that is its channel appointed path.There is a searcher periodically to carry out channel search to received signal, detects in the channel some the newest delays in strong path.A plurality of trackers that each channel path is one are adjusted between each time search that searcher is carried out and are selected specified delay.Delay controller that is connected with tracker with searcher searcher is obtained these the newest delay in strong path compare with selecting specified delay, and only newly just reassign this when postponing to select minimum that specified delay differs by more than a preliminary election and select specified delay with this new delay with one at one.
Characteristics of the present invention are that delay controller selects specified delay to compare with each the delay in detected each the strongest path, to determine the new delay of one of the most approaching selection specified delay.Delay controller determines that determined immediate new delay is to belong to same path with a selection specified delay, if detected immediate new delay and this selection specified delay differ the minimum less than preliminary election.
Another characteristics of the present invention are, delay controller is with the immediate selection specified delay of reassigning in the detected new delay.
According to another aspect of the present invention, the Receiver of Direct-sequence Spread Spectrum of working in a multipath fading channel that is disclosed comprises a Rake receiver with a plurality of rake fingers.Each rake finger carries out demodulation to the received signal from one of a plurality of channel paths.The output of these rake fingers is combined.Each rake finger utilizes one to select specified delay synchronous with the delay that is its channel appointed path.There is a searcher periodically to carry out channel search to received signal, detects in the channel some the newest delays in strong path.Delay controller that is connected with searcher will obtain from searcher these the newest delay in strong path compare with selecting specified delay, with the immediate selection specified delay of reassigning in the new delay.
According to another aspect of the present invention, the method of the received signal of the processing that is disclosed in a multipath fading channel comprises the following steps: to utilize some to select specified delay synchronous with the delay of a plurality of channel paths respectively, to the receiving signal demodulation from each channel path; Periodically carry out channel search, detect in the channel some the newest delays in strong path; Between each secondary channel search, adjust and select specified delay; And with these the newest delay in strong path compare with selecting specified delay, only newly just reassign this when postponing to select minimum that specified delay differs by more than a preliminary election and select specified delay with this new delay with one at one.
According to another aspect of the present invention, the method of the received signal of the processing that is disclosed in a multipath fading channel comprises the following steps: to utilize some to select specified delay synchronous with the delay of a plurality of channel paths respectively, to the receiving signal demodulation from each channel path; Periodically carry out channel search, detect in the channel some the newest delays in strong path; And with these the newest delay in strong path compare with selecting specified delay, with the immediate selection specified delay of reassigning in the new delay.
From following explanation and accompanying drawing, can be clear that other characteristics of the present invention and advantage.
Brief Description Of Drawings
Fig. 1 is the block diagram of Receiver of Direct-sequence Spread Spectrum of the present invention;
Fig. 2 is the block diagram of the baseband processor among Fig. 1; And
Fig. 3 is the flow chart that the rake finger register control among Fig. 2 is carried out.
Detailed description of the invention
Fig. 1 illustration direct sequence spread spectrum of the present invention (DS-SS) receiver 10.Receiver 10 is worked in the channel that the multipath decline is arranged, and receives the RF signal that sends by antenna 12.The RF signal is down-converted to base band by parts 14 from RF, and resulting complex baseband signal offers baseband processor 18 by line 16.Though illustrative for simplicity is a single antenna receiver, is appreciated that the present invention can be used to have the receiver of array antenna 12, thereby just has one group of signal component to offer processor 18.
Fig. 2 at length illustration baseband processor 18.Be added to baseband signal matched filter 20 filtering of mating on the line 16 with chip (chip) impulse waveform.If channelizing filtering is talked about fully in RF part 14, this filter can save.Be sampled into each chip through the baseband signal of filtering by parts 22 K sampling point arranged.In one embodiment, K equals 8.Signal through sampling is added on Rake receiver 24, delay tracker 26 and the down-sampled device 28.Down-sampled device 28 offers delay searcher 30 with each chip L sampling point of the down-sampled one-tenth of signal, and wherein L is certain integer less than K.In one embodiment, L equals 2.Delay tracker 26 and delay searcher 30 are connected to delay controller 32 again, and delay controller 32 is connected to Rake receiver 24 and delay tracker 26 conversely again.
Be appreciated that with the related delay of multi-path channel and with the related delay of the multi-path component that on this multi-path channel, receives be identical.Therefore, term " path delay " and " component delay " can be exchanged.
According to the present invention, for Rake receiver 24 appointments, definite by rake finger register control 32 by these specific delays of delay tracker 26 fine settings, rather than definite by searcher 30.Delay searcher 30 is periodically searched in very wide channel delay span, detects new channel path and postpones.Because searcher 30 is searched in the scope that very wide channel may postpone, in order to accelerate search procedure and simplification realization equipment, search is as parts 28 sampling is reduced to such carrying out than low sampling rate shown in each chip L sampling point.The sample rate reduction causes delay searcher 30 accurate inadequately.When searcher 30 has been finished once new search, if some stronger channel paths, just can updating delay tracker 26 and those used delays of Rake receiver 24.According to the present invention, the delay that tracker 26 is followed the tracks of and finely tuned is upgraded in the 30 detected delays of delay controller 32 usefulness searchers, makes this renewal process can not cause the decreased performance of Rake receiver 24.
This flow chart of Fig. 3 has supposed that delay searcher 30 finds that M postpones to be the new channel path of S (i), wherein 1≤i≤M after any search.Suppose that also N of delay tracker 26 tracking postpone to be the path of T (j), wherein 1≤j≤N before finishing current search.In a typical embodiment, postponing S (i) and T (j) is unit in the sampling point, and one of them sampling point is 1/8 of a chip period.The new detected delay that variable S (i) expression searcher 30 is found.The current delay that variable T (j) expression delay tracker 26 is followed the tracks of and adjusted.
Referring to Fig. 3, postpone and be added on the square frame 40 from M of searcher 30 from N delay of delay tracker 26, form a controller matrix that N is capable, M is listed as.In this matrix every-individual unit is the absolute value of S (i)-T (j).Following illustration a example for M=4 and N=3.
S(1) S(2) S(3) S(4)
T(1) |S(1)-T(1)| |S(2)-T(1)| |S(3)-T(1)| |S(4)-T(1)|
T(2) |S(1)-T(2)| |S(2)-T(2)| |S(3)-T(2)| |S(4)-T(2)|
T(3) |S(1)-T(3)| |S(2)-T(3)| |S(3)-T(3)| |S(4)-T(3)|
Variable m is initialized as zero at square frame 42.Square frame 44 adds 1 with variable m.Square frame 46 variable z are set to equal minimum unit in the controller matrix that square frame 40 forms.The z of unit is corresponding to the searcher 30 detected nearest new delays of following the tracks of from one of delay tracker 26 of delay.For example, if first z is positioned at capable sequence number 2 and row sequence number 3, Here it is refers to that searcher 30 the detected the 3rd detects the path and the second tracker path is immediate.At square frame 48, value r is set to the capable sequence number of the unit of the minimum determined at square frame 46, and variable c is set to the row sequence number of the unit of minimum in the controller matrix that square frame 46 is determined.Then, all unit of square frame 50 deletions in the capable r of the controller matrix that square frame 40 forms and all units that are listed as in the c.Amended like this matrix becomes:
S(1) S(2) S(4)
T(1) |S(1)-T(1)| |S(2)-T(1)| |S(4)-T(1)|
T(3) |S(1)-T(3)| |S(2)-T(3)| |S(4)-T(3)|
As a result, if redistribute second tracker, it will be re-assigned to follows the tracks of the delay of the 3rd searcher.Just prevented from again other delays to be distributed to second tracker or again other trackers have been distributed in the new delay of the 3rd searcher at square frame 50 these yuan of deletion.
Control proceeds to decision block 58 from square frame 56 by node A, determines whether also have remaining unit in gating matrix.If any, control just turns back to square frame 44.So, above repeating to square frame 44 to square frame 56 described processing, units all in the controller matrix is all deleted.If M=N or M<N, Rake receiver 24 and delay tracker 26 have just all been distributed in detected these paths of searcher, and processing procedure is finished.Otherwise, just there is the path of appending need distribute to some trackers, it is such that following mask body illustrates.
If find in the controller matrix, there be not other yuan again in decision block 58, so decision block 60 determines whether m=M.If like this, this processing procedure has just been finished.Yet, under the situation that number of path reduces, if i.e. M<N, so have N-M tracker both affirmation be not assigned to new path with original delay yet.Therefore these trackers and their corresponding rake finger just disconnect at square frame 62, thereby this routine stops at square frame 64.On the contrary, if M>N just illustrates that searcher 30 detected new routes are more than these tracker 26 current paths of following the tracks of.Be not equal to M if draw m, this situation just occurs at square frame 60.In this case, variable m adds 1 at square frame 66.Square frame 68 row sequence number c are set to any row sequence number c that does not before also have distribution at square frame 68 from 1 to M.Tracker T (m) is so give delay S (c) in square frame 70 assignments.Then, decision block 72 determines whether m equals M.If like this, control just forwards square frame 64 to, and routine stops.If not so, control just turns back to square frame 66, continues to give tracker 26 and rake finger with detected all the other the path assignments of searcher.
Proceed to square frame 54 from square frame 52 and mean that the unit of the minimum the matrix is above thresholding δ.Therefore, all remaining units also will this means that remaining searcher postpones assignment give some delay trackers above δ.
As seen from the above description, the rake finger register control makes the precision reduction of tracker recited above and the unnecessary problem of reorientating reduce to minimum.Unit minimum in the selection control matrix has guaranteed there be not unnecessary reorientating rake finger.Before reassigning tracker, with δ relatively, guaranteed that tracker has only where necessary just assignment again.Specifically, this method postpones identifying postponing approaching mutually searcher and tracker, does not only just specify the new detected delay of searcher for tracker simultaneously at channel path.
The DS-SS receiver can be realized without delay tracker.Directly use the detected path of searcher and do not finely tune and change rake finger into.This is particularly suitable for searcher hardware and allows searcher to have many sampling points to carry out the situation of work with each chip.In the receiver of design like this, reduce problem with regard to the precision of being discussed above not existing.Even searcher has good resolution (each chip has enough sampling points), still can utilize delay tracker that the delay of searcher between upgrading estimated can be more accurate.Therefore, still can eliminate the unnecessary problem that rake finger is reorientated with baseband processor 18 designed according to this invention.
Though the present invention describes with the Rake receiver of a plurality of rake fingers, the Rake that the present invention also can be used for other formation receives.For example, Rake receiver can be implemented as a sliding correlation detector and connects a tapped delay line after again.Sliding correlation detector produces some and in succession the corresponding despread values of length of delay.These despread values are kept in the tapped delay line then.A rake finger just supplies Rake to merge the position of the tap of usefulness corresponding to extraction on the tapped delay line.
Key of the present invention a bit is the rake finger that assigns to the existing channel path not to be upset the assignment again of demodulation.This means the delay estimation that not only keeps from delay tracker, but also be preserved for other demodulating informations of this rake finger, for example channel coefficients is estimated, perhaps also has automatic frequency correction (AFC) to estimate.Adopt traditional Rake to merge, despread values will multiply by the complex conjugate of respective channel coefficients.Channel coefficients can utilize the channel of piloting, the code element of piloting and/or decision-feedback are estimated.In addition, consider the imperfection of local oscillator or the Doppler frequency shift in channel path, may need AFC estimates, estimate and/or phase estimation such as frequency error, channel estimating and AFC proposed on December 16th, 1997, transfer the application's assignee's unsettled U. S. application No.08/991, in 770 " at the method and apparatus of DS-SS cdma receiver medium frequency lockon and follow " (" Method and Apparatus forFrequency Acquisition and Tracking in DS-SS CDMA Receivers ") detailed argumentation is arranged, this application is classified reference here as.Therefore, in Fig. 3, square frame 56 is not only to keep and is postponed to estimate, but also keeps other estimations related with rake finger.
When the assignment of some rake fingers being carried out at the square frame 54 of Fig. 3 again, channel and AFC estimate and must reinitialize.The simplest solution is that channel coefficients is set to zero, and also AFC phase place and frequency error estimate to be set to zero.Yet, become accurately to these estimations before, have one section delay, thereby incured loss through delay effective use of the rake finger of assignment recently.In order to reduce this delay,, these estimations are initialized as nonzero value according to the present invention.For channel estimating, channel coefficients is initialized as an initial measurement, perhaps guard a bit again, and be noisy to consider this measured value.For example, in the system that a channel of piloting such as IS 95 is arranged, available and this channel of piloting initially relevant come the Initial Channel Assignment coefficient.
For AFC (if any), frequency error estimate to be initialized as obtain from another rake finger (for example the strongest rake finger) or from certain one of estimating to obtain according to the comprehensive frequency error of a plurality of rake fingers is existing estimates.If AFC uses a phase-locked loop, phase place just can be initialized as the phase place of the channel coefficients value of at first measuring.For example, in the system that a channel of piloting such as IS 95 is arranged, availablely come the initialization phase estimation with the initial relevant phase place of this channel of piloting.Therefore, the demodulating information that obtains from first group of channel path (for example existing rake finger) usually can be used for initialization to the demodulation from second group of channel path (for example new rake finger).Each group can contain one or more units.
The initialization of rake finger also occurs in receiver when connecting at first.For this situation, also can adopt according to initial measurement result or one group of initial measurement result and carry out initialization.For AFC, frequency error is estimated to be initialized as a value that obtains from certain initial coarse frequency estimation error or is initialized as zero.
As the personnel that are familiar with this technical field can see, the present invention can be presented as certain methods or equipment.Therefore, the present invention can be rendered as fully with hardware implement, fully with software implementation or with the form of software and hardware Joint Implementation.
The invention has been described in conjunction with Fig. 3 of the flow chart of illustration one embodiment of the invention with top.Very clear, the combination of some square frames can realize with computer program instructions in each square frame of flow chart and the flow chart.These represent that the program command of each step can offer a processor and form an equipment.
Therefore, some square frame supports of flow chart carry out these appointed functions device combination and carry out the combination of the step of these appointed functions.The combination that is further appreciated that some square frames in each square frame of flow chart and the flow chart can realize with the system based on specialized hardware of put rules into practice operation or step, also can realize with the combination of specialized hardware and computer instruction.
Therefore, disclosed is a kind of is the new Receiver of Direct-sequence Spread Spectrum that postpones of rake finger assignment by delay searcher and delay tracker reciprocation.
Claims (31)
1. Receiver of Direct-sequence Spread Spectrum of in a multi-path channel, working, described Receiver of Direct-sequence Spread Spectrum comprises:
A Rake receiver (24) selects specified delay to be synchronized on a plurality of channel paths by utilizing some, merges the despread values from these channel paths, demodulation to received signal;
A searcher (30) is periodically carried out channel search to received signal, detects the new delay in path in the multipath channel;
A plurality of trackers (26) are followed the tracks of the delay of selecting appointment between each time search that searcher is carried out, it is characterized in that:
A delay controller that is connected with tracker with searcher (32), if the delay of selecting appointment not in the predetermined threshold of at least one new delay, described delay controller is just replaced the delay of selection appointment with new delay.
2. the Receiver of Direct-sequence Spread Spectrum of claim 1, wherein said delay controller selects the delay of appointment to compare each new delay and each, with new a delay of the delay of determining the most approaching selection appointment.
3. the Receiver of Direct-sequence Spread Spectrum of claim 2, if immediate new delay and this selection specified delay differ the threshold value less than preliminary election, then wherein said delay controller determines that the delay of an immediate new delay and a selection appointment belongs to same path.
4. the Receiver of Direct-sequence Spread Spectrum of claim 2, if the difference of immediate delay and the delay of selecting appointment greater than predetermined threshold, then delay controller is reassigned the delay of selected appointment with immediate new delay.
5. the Receiver of Direct-sequence Spread Spectrum of claim 2, wherein said Rake receiver has a plurality of rake fingers, and each rake finger that wherein is assigned to channel path is synchronous with the delay of the delay of selecting appointment and described channel path.
6. the Receiver of Direct-sequence Spread Spectrum of claim 1, wherein said delay controller is by the new initialization demodulating information that postpones.
7. the Receiver of Direct-sequence Spread Spectrum of claim 6, wherein said initialization newly postpones corresponding channel coefficients measurement result and carries out with one according to one.
8. the Receiver of Direct-sequence Spread Spectrum of claim 6, wherein delay controller is estimated to equal by second estimating that a different rake finger uses by setting first, and that comes that initialization is assigned to that a new rake finger that postpones uses first estimates.
9. Receiver of Direct-sequence Spread Spectrum according to claim 1,
Wherein, if the delay of selecting appointment within a new predetermined threshold that postpones, delay controller is not reassigned the delay of selecting appointment.
10. Receiver of Direct-sequence Spread Spectrum a multi-path channel job comprises:
A Rake receiver (24) selects the delay of appointment to be synchronized on a plurality of channel paths by utilizing some, merges the despread values from these channel paths, demodulation to received signal;
A searcher (30) periodically carries out channel search to received signal, detects in the multichannel some the newest delays in strong path; It is characterized in that:
A delay controller that is connected with searcher (32) selects the delay of appointment to compare with each the new delay that searcher obtains, with immediate delay of reassigning the selection appointment in new the delay.
11. the Receiver of Direct-sequence Spread Spectrum of claim 10 further comprises a plurality of trackers of one of each channel path, is used for following the tracks of between each time search that searcher is carried out the delay of selection appointment.
12. the Receiver of Direct-sequence Spread Spectrum of claim 11, if the delay of wherein immediate new delay and this selection appointment differs the threshold value less than preliminary election, described delay controller determines that immediate new delay and the delay of selecting appointment belong to same channel path.
13. the Receiver of Direct-sequence Spread Spectrum of claim 10, wherein said Rake receiver have a plurality of rake fingers of respectively distributing to one of a plurality of channel paths, each rake finger is synchronous with the delay of selecting specified delay and described channel path.
14. the receiver of claim 10, wherein said delay controller is by the new initialization demodulating information that postpones.
15. the receiver of claim 14 is wherein according to carrying out initialization with a corresponding channel coefficients measurement result of new delay.
16. the receiver of claim 14 wherein carries out initialization according to some existing estimations.
17. Receiver of Direct-sequence Spread Spectrum according to claim 1, wherein:
Delay controller is that a plurality of rake fingers are reassigned the selection specified delay to analyzing from the new delay of searcher with from the selection specified delay of tracker according to the new delay that receives from searcher.
18. the method for the received signal of a processing in a multipath fading channel comprises the following steps:
It is synchronous to utilize some to select specified delay and channel path to postpone, to from each receiving signal demodulation in a plurality of channel paths;
Periodically carry out channel search, detect the new delay in the described channel; With
Between each secondary channel search, adjust the delay of selecting appointment, it is characterized in that:
Select specified delay to compare each new delay and each, only when a new delay selects specified delay to differ by more than the threshold value of a preliminary election with one, just reassign the delay that this selects appointment with this new delay.
19. comprising, the method for claim 18, wherein said comparison step select specified delay to compare each new delay and each, with the step of the new delay of determining one of the most approaching selection specified delay.
20. the method for claim 19, wherein said comparison step comprise, if immediate new delay and one select specified delay to differ threshold value less than preliminary election, just determines that immediate new delay and this selection specified delay belong to the step in same path.
21. the method for claim 18, wherein said comparison step is reassigned the delay of selecting appointment with immediate in the detected new delay.
22. the method for claim 18, wherein said comparison step comprise the step by new delay initialization demodulating information.
23. the method for claim 22, wherein said initialization is carried out with a corresponding channel coefficients measurement result of new delay according to one.
24. the method for claim 22, wherein initialization comprises corresponding to the demodulating information of new delay, and first estimation that setting is used by the rake finger that is assigned to a new delay equals the second corresponding estimation by different rake fingers uses.
25. the method for the received signal of a processing in a multipath fading channel, described method comprises the following steps:
Utilize some to select the delay of one of specified delay and channel path synchronous, to receiving signal demodulation from each channel of a plurality of channels; With
Periodically carry out channel search, detect the new delay in the described channel; It is characterized in that:
To newly postpone to compare, with the immediate selection specified delay of reassigning in new the delay with selecting specified delay.
26. the method for claim 25, described method also are included between each secondary channel search and adjust the step that these select specified delay.
27. the method for claim 26, wherein said comparison step comprises, if determined immediate new delay and one select specified delay to differ threshold value less than preliminary election, just determine that immediate new delay and this selection specified delay belong to the step in same path.
28. the method for claim 25, when wherein said comparison step only selects specified delay and this to select specified delay to differ by more than the threshold value of a preliminary election near one, just reassign this selection specified delay with this immediate new delay in new the delay.
29. the method for claim 25, wherein said comparison step comprise the step by new delay initialization demodulating information.
30. the method for claim 29, wherein said initialization is carried out with a corresponding channel coefficients measurement result of new delay according to one.
31. the method for claim 29, wherein initialization comprises corresponding to a new demodulating information that postpones, and first estimation that setting is used by new rake finger that postpones of an appointment equals the second corresponding estimation by different rake fingers uses.
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Application Number | Priority Date | Filing Date | Title |
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US09/168,233 US6560273B1 (en) | 1998-10-07 | 1998-10-07 | Delay searcher and delay trackers interaction for new delays assignment to rake fingers |
US09/168,233 | 1998-10-07 |
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CN100385813C true CN100385813C (en) | 2008-04-30 |
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AU6402899A (en) | 2000-04-26 |
ATE271281T1 (en) | 2004-07-15 |
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BR9914324A (en) | 2001-06-26 |
JP2002527925A (en) | 2002-08-27 |
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HK1046071B (en) | 2008-12-24 |
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